samber/oops Structured Error Handling

Persona: You are a Go engineer who treats errors as structured data. Every error carries enough context — domain, attributes, trace — for an on-call engineer to diagnose the problem without asking the developer.

samber/oops Structured Error Handling

samber/oops is a drop-in replacement for Go's standard error handling that adds structured context, stack traces, error codes, public messages, and panic recovery. Variable data goes in .With() attributes (not the message string), so APM tools (Datadog, Loki, Sentry) can group errors properly. Unlike the stdlib approach (adding slog attributes at the log site), oops attributes travel with the error through the call stack.

Why use samber/oops

Standard Go errors lack context — you see connection failed but not which user triggered it, what query was running, or the full call stack. samber/oops provides:

• Structured context — key-value attributes on any error
• Stack traces — automatic call stack capture
• Error codes — machine-readable identifiers
• Public messages — user-safe messages separate from technical details
• Low-cardinality messages — variable data in .With() attributes, not the message string, so APM tools group errors properly

This skill is not exhaustive — refer to library documentation and code examples for more information:

• For Go package docs, symbols, versions, importers, and known vulnerabilities, → See samber/cc-skills-golang@golang-pkg-go-dev skill (godig), preferred over Context7 for Go package facts.
• To navigate this library's usage in your own code (definitions, call sites, diagnostics), → See samber/cc-skills-golang@golang-gopls skill (gopls).
• Context7 remains a fallback for docs not indexed on pkg.go.dev.

Core pattern: Error builder chain

All oops errors use a fluent builder pattern:

err := oops.
    In("user-service").           // domain/feature
    Tags("database", "postgres").  // categorization
    Code("network_failure").       // machine-readable identifier
    User("user-123", "email", "[email protected]").  // user context
    With("query", query).          // custom attributes
    Errorf("failed to fetch user: %s", "timeout")

Terminal methods:

• .Errorf(format, args...) — create a new error
• .Wrap(err) — wrap an existing error